Autocollimating button and light



Jan. 29, 1946. /R. IN. FRERES Filed Feb. 5, 1944 Fig.1

Patented Jan. 29, 1946 UNITED STATES AUTOCOLLIMATING BUTTON AND LIGHT SHIELD THEREFOR Robert N. Freres, Rochester, N. Y., assignor to the United States of America, as represented by the Secretary of War Application February 5, 1944, Serial No.

6 Claims.

This invention relates to buttons and'm'ore particularly, it is directed to autocollimating buttons adapted to translate invisible light into vis-' ible light.

One of. the properties which autocollimating buttons must have is complete absorption of all light rays, which would normally hit the phosphor or other light generating surface and be reflected in a diffused state directly therefrom. This property is attained by placing adirect light ray shield at the focal point of a parabolic r-' iiector, which shield has assoeiated,'or may have integral therewith, a phosphor back which faces the parabolic reflector. Hence, none but li ht reflected from the back is returned by the button.

In the application of Neil O. Broderson, Serial No. 521,292 filed February 5, 1944, there is disclosed an autocollimating button including two lens elements having a recess in one of the elements, with light sensitive material in the recess and a plug mounted in the recess for sealing the light sensitive material therein, said plug having black lacquer thereon serving as a direct ray shield shutting off from a front view the light generating material. The two lens elements are frictionally welded together by means of an apparatus disclosed in the application of Louis Gertzog, Serial N 0. 474,761, filed February 4, 1943. The plug having the black lacquer thereon is provided in the recess for preventing dispersing of the light generating material, duerto the violence in the welded friction contact zone of the two lens elements, which contact zone is in general coincidence with the point 'of application of the light generating material. I

It has been discovered that a light ray shield in the form of a piece of flexible material such as black cardboard or other suitable paper may be substituted for the plug having the black lacquer thereon as in the above-mentioned application to Broderson, which improved shield prevents the dispersion of light sensitive material during the welding of the lens elements and is not welded to the lens elements as the plug above referred to.

It is therefore an object of the invention to provide an improved light ray shield in an autocollimating button of the type in which two lens elements are frictionally welded together and having a recess in one of the lens elements, with light generating material in the recess, said improved light ray shield being in the formof a piece of black flexible material such as cardboard fitted into the recess for preventing the dispersion of the light sensitive material during the welding of the lens element together.

Another object of the invention is to provide an improved light ray shield fitted into a recess in one of dual lens elements of an autocollimating button, and having light generating coated on the shield. I a

With the'above and other objects and. advantages in view, the invention consists of certain features of construction and operation of parts, which will hereinafter be described and shown in the accompanying drawing, in which:

Figure l'is a top plan view of a machine hav ing two chucks rotatably mounted thereon with dual parts of an autocollimating button to be welded together mounted in the chucks;

Figure 2 is an enlarged vertical sectional view of the dual parts of the button, showing a recess containing light generating material in one of the parts of the button and having the improved light ray shield fitted into the recess for sealing the light generating material in the recess prior to welding the dual parts of the button together;

Figure 3 is an enlarged view of a completed button after the dual parts of the button have been welded together and embodying the improved light ray shield therein; and r I Figure 4 is an enlarged perspective detail view of the improved light ray shield having light gen-, erating material coated thereon.

Referring more specifically to the drawing, there is shown in Figure 1 a frame I having ;a driven shaft 2 and revoluble shaft 3 mounted thereon. The driven shaft 2 has a chuck 4 mounted on its inner end and a pulley 6 mounted on its outer end, which pulley 6 is driven at a suitable constant speed for rotating the driven shaft 2 by a motor I through a belt 8. The chuck 4 on the inner end of shaft 2-holds a portion or lens element 9 of the improved autocollimating button indicated generallyby A in Figures 2 and 3, and the revoluble shaft 3 is provided with a sleeve I and a brake ll, here illustrated as being of the flyball governor type inertia brake, but any suitable type of braking means may be em ployed. A chuck is mounted on the inner end of the sleeve ID in opposed relation to the chuck 4 on the driven shaft 2 and holds a portion or lens element l2 of the button. The sleeve ill. is 5 slidably mounted on the revoluble shaft 3 and is actuated on the shaft 3by means of a pivoted lever l3 for moving the lens element l2 of the button into and out of frictional contact with the revolved lens element 9.

The button portions or lens elements 9 and I2 held in chucks 4 and 5, respectively, are more particularly illustrated in Figure 2. The upper driven button portion 9 includes an autocollimating optical outer surface l4 and an inner sur face IE to be welded to the inner surfac iii of button portion 12. The inner surface l5 of button portion 9 is slightly convex to compensate for differential velocity in the welding processasthe outer part of 'the convex surface It away from the center of rotation moves considerably material faster than the part near the center. A recess socket I1 is centrally formed in the fiat surface l6 of the ulndriven bottom ortion m, with the inner surface or bottom "18 of therecess H being curved and covered with phosphorescent or other 5, light generating material l9. The improved light ray-shield 20 to which this jj invention is particularly directed is made of :any

suitable dark, flexible material such as paper,

here illustrated as being in .Etorm dfa bl'ack locardboard disc member which is snugly fitted into the recess l1 formed in the bottom portion or lens element l2 of the button sA,whereby.the light generating material I9 is sealed in the .re-

cess l1 and the possibility of the light generating -15 material becoming distorted during the process of welding the button portions :o'r'members 9 and 4:2 together is avoided. The black cardboard disc 20 serves as a directsli'ght may shield :at the focal point, of the :button-A, shutting 'offsfl'bm a front 2 vlewlthelightgenerating mattarial4 9. i

The improved light :ray shield M may be directly coated on its back with the light generating material .l:9 illustrated in Figure 4 and mounted in the recess is? of the bottom button as member 12, :instead of the :light generating material 18 being first provided in the :recess ill, with the shield 20 iplaced over the slight :generating material as shown Figures 12 and 3..

In forming the improved autoeollimating 'but- 9 ton A, Figures 2 and after the Ilightgenerat- 'in'g material 19 :has been placed the bottom button member 12 and the light may shield 29 has been fitted into the' recess overstheilightgencrating material m, or the light shield zctihav- 3.?

ing *the ligh't generating material 19 eoaitelmn its back, Figure 4, is fitted into the rece'ss II, the button member 4-2 is mounted on the chuck 5 and the upper button' member "e :is mounted on chuck 4, with the surfaces t5 and is of imambers "9 and 1-2, fesp'eoti velmfloeihg i-n opposed relation to each other. Upon starting the motor 1, the driven shaft '2 is rotated at any suitable constant high speed through the belt 8 and 'Iiuh Ray '6, thereby rotating chuck t holding thebutton portion 9. "The lever l s is then operated by the hand to move the sleeve I 0 i-nwardlyjwnereby the inner surface 4 6 of the non-driven button member 12 in "chuck 5 "is "caused to engage the inner surface f5 or button member 9, thus setting up friction between surfaces and "I? of the button members "9 and 1 2, respectively, with the production of heat, causing the melting of these surfaces 1 5 and 1 6, thus effecting the cementing or Welding of the button members 9 and P2 toet-her.

The 'light my shield '20 prevents "the light gen-- erating material 1'9 in the recess I from spreading all over the surface It of button-portion 12 upon the button portion 9 being brought "intercom tact with non-rotating bottom portion i2.- As the light ray shield 21! fits exactly mm the recess 11, it 'will be "temporarily held therein by friction of its outer edge against the surface of the portion of the button member 1'2 surrounding the recess. :The light ray shieldffl is fitted into the recess 1-! in such a manner as to be beneatn the upper surface l6 of button menrber 1'2 and is not welded to the button as the plug in the auto'collimating button disclosed in the'above; mentioned application of Broderson, smear-em being suiflci'ently flexible to a degree that will permit it to be litt'e'd into the recess 17.

fteri'al activated invisible rays such as infra red 'rays'proj'ected from any direction upon the rautocollimatmglsurface of the lens body. In this manner a marking device is provided which need not "be exposed to visible light to produce a concentrated beam of lightan'd, therefore, willwescape detection by occupantssof aircraft (other persons not in the :line of the concentrated them.

It will thus be seen that there i hereiniproyided an autocolli-matingbutton embodying a new and eficient form'of lightray shield thereon and adapted to translate iinuisible light rintowise iblalight. Even though ithereghas :h'erein been shorthand. described-certain features of construc- :tion, and operation of, parts, :it isnevesthel'es'sito be understood that various changes may bo-made therein, .if the changes :do not-depart tram-the spirito'rscopeofthe claim's. i. i Having thus described invention, w hait I claim :as new and to secure-by-mtersi'au BlItil'S'L. 1

L An eautocollimating button comprising a pair :of :lens :members bonded together, one of said members being provided with an autocoh limatin'g outer surface, a recess termed in iene' of saiid ine'mbers, =a "light generating substance bositioned in said recess, and a light sl-i ilii 1 oos'itioned 'i-n'said recess in juxtaposition-with said light generating substance and between said sea stance and said autccollimatingsuriace. 2 autocellimating button comprising a pair of lens members bonded together; one oi'sai'd members being provided *With an autocollimating outer surface, a recess formed mm-re of said members, a light 'ra'y shield mcunted'in said jre= cess, the race "of said shield *a'diacent said autocollimating surface being provided with a light absorbing surface and the oppositeffa'ce of said shield -b'eing=provi'c'led"witna light-"generating surg, ftrnn autocollimatmg buttonin accordan e with claim 2 and "characterized in that the light ray-shield comprisesaflexibledisc; 4; I autoco'liimatin'g buttoh in accordance with claim 2 and characterized in theft the light ray shield comprises a black cardboard *disc prov idedwith a coatin of light generating mater ial ononeiacethereof. a r 1 5. autocollima'ting button comprising a pai of lens members bonded togethery ohe of said .lens members "being provided with an rauitocollimating outer surfiace, a recess formed in one of .said members, light generating material spositioned .in said recess :and guard means ipositioned between :said light generating material and said autocollimatimg surface :for protecting said light generating material.

6. autocollimating button in accordance with claim -5- characterized in that the guard means comprises a flexiblelight absorbing disc. ROBERT 1 

